In industry, and in particular semiconductor manufacturing, cryogenic fluids are often employed when it is desired to cool a tool or a workpiece to a very low temperature. This cooling is normally achieved by the application of a cryogen such as liquid nitrogen to the object to be cooled. The cryogen may be supplied to an operator from a central reservoir, or from a well insulated supply pipe, through flexible tubing. Due to the very low temperature of the cryogen the tubing becomes hard and brittle and attracts condensation. This hardness of the tubing causes inconvenience to the operator and the condensation collecting on the tubing presents a hazard to operators of electrical machinery or tools as well as being highly inconvenient.
Cryoprobes form the operating portion in the use of cryoganic fluids, and take the form of a chamber into which the cryogenic fluid is fed, the chamber having a wall through which heat exchange can take place between the cryogenic fluid and the object to be cooled. Existing forms of cryoprobes, however, have the disadvantage that this heat exchange causes the cryogenic fluid to boil in the area adjacent the chamber wall, which creates in that area a low-temperature gas. This has an insulating effect between the chamber wall and the main body of the cryogenic fluid, with the result that heat exchange for further evaporation of the cryogenic fluid is hampered. This in turn reduces the cooling effect of the cryoprobe.